The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
A recent increase in oil price has led automobile companies throughout the world to infinite competition toward improvement of fuel efficiency and efforts have been made to downsize engines to reduce weight in order to improve fuel efficiency.
Meanwhile, among various fuel efficiency improvement methods, automatic transmission configured to perform multiple stages have been developed to improve fuel efficiency as well as to secure operability.
However, as gear shift stages are increased, the number of internal components constituting an automatic transmission may also be increased, which negatively impacts on mountability, cost, weight, and transmission efficiency.
Thus, in order to improve fuel efficiency through multiple gear shift stages, we have discovered that it may be important to devise a gear train structure capable of obtaining maximum efficiency with reduced number of components.
The foregoing is intended merely to aid in the understanding of the background of the present disclosure, and is not intended to mean that the present disclosure falls within the purview of the related art that is already known to those skilled in the art.